Japanese Patent Application No. 2003-024177 discloses four-wheel individual steering and individual braking/driving control which maximizes vehicle body generating force in the process of realizing a desired direction in which vehicle body generating force acts, and a yaw moment. In this technique, a utilization factor of a road surface friction coefficient μ between a tire of each wheel and the road surface (hereinafter referred to as μ utilization factor) derives an optimum control rule which minimizes μ utilization factor on the assumption that the direction in which tire generating force acts is considered as a constant manipulated amount.
Further, Japanese Patent Application Laid-Open (JP-A) No. 11-348753 proposes control of braking force based on slip ratio target values of respective wheels for obtaining target yaw moment, vehicle longitudinal force and lateral force being calculated based on variations of yaw moment, vehicle longitudinal force and lateral force to small variations in the slip ratio between the respective wheels.